KR101464027B1 - Apparatus and method for manufacturing liquid crystal panel - Google Patents

Abstract

The occurrence of foaming in the liquid crystal layer of the liquid crystal panel is suppressed as much as possible in the light irradiation treatment for polymerizing (curing) the ultraviolet reactive material.
The liquid crystal panel 3 in which the liquid crystal 3c including the ultraviolet ray reaction material is sealed between the two light transmitting substrates (glass substrates) 3a and 3b is irradiated with light from the light irradiating unit 1 while applying a voltage do. As the light source 1a of the light irradiating unit 1, when the irradiation amount a of the light in the wavelength region contributing to the reaction of the light reactive substance in the liquid crystal panel is equal to the energy amount A required for the reaction of the light reactive substance, Is smaller than the amount of energy B required for the amount of gas generated in the interlayer insulating film that absorbs the light in the wavelength region to penetrate into the liquid crystal layer to reach the foaming in the liquid crystal layer A lamp having an emission spectrum (for example, a rare gas fluorescent lamp) is used. Thus, the occurrence of foaming in the liquid crystal layer can be suppressed.

Description

TECHNICAL FIELD [0001] The present invention relates to an apparatus and a method for manufacturing a liquid crystal panel,

[0001] The present invention relates to an apparatus and a method for manufacturing a liquid crystal panel of a multi-domain vertical alignment (MVA) type, and more particularly to a liquid crystal display apparatus having a liquid crystal having an orientation property, And a method of manufacturing an apparatus for manufacturing a liquid crystal panel by forming an alignment film on a glass plate by polymerizing an ultraviolet reaction material by irradiating the liquid crystal panel with ultraviolet rays.

Fig. 10 shows a configuration example of a liquid crystal panel. The liquid crystal panel 50 has a structure in which liquid crystal 58 is sealed between two light transmitting substrates (first glass substrate 51 and second glass substrate 52) A plurality of active elements (for example, a thin film transistor: a TFT 53) and a liquid crystal driving electrode 54 (a transparent electrode ITO) are formed and an orientation film 56 is formed thereon. A color filter 57, an orientation film 56, and a transparent electrode (ITO) 55 are formed on the second glass substrate 52. The liquid crystal 58 is sealed between the alignment films of the both glass substrates 51 and 52, and the periphery is sealed with the sealant 59.

In recent years, in order to increase the aperture ratio of the liquid crystal panel, there is a case where an interlayer insulating film is provided between the active element (TFT 53) and the liquid crystal driving electrode 54 as shown in Patent Document 5.

Fig. 11 schematically shows an active element and its peripheral configuration example in the case of providing an interlayer insulating film.

The TFT 53, which is an active element, is configured as follows.

A gate insulating film 532 made of, for example, an SiN _x film is provided on the gate 531 made of, for example, Ta, Mo, Al or the like formed in one pixel region. And a semiconductor layer 533 made of, for example, amorphous silicon is superimposed on the upper portion. A source 534 and a drain 535 made of, for example, a low-resistance Al-based alloy are provided in a part of the semiconductor layer 533.

A source wiring 541 made of, for example, a low-resistance Al-based alloy layer is provided on the source 534 of the TFT 53 constructed as described above. The drain 535 is provided with, for example, A drain wiring 536 is formed. Although the illustration is omitted, a gate wiring is provided in the gate 531.

The TFT 53, the source wiring 541, the drain wiring 536, and an interlayer insulating film (organic insulating film) 500 made of, for example, acrylic resin are provided so as to cover the upper portion of the gate wiring. A part of the interlayer insulating film 500 is removed by a photoetching process, and a contact hole 500a is formed on the drain wiring 536. [ A liquid crystal driving electrode 54 (a transparent electrode (ITO)), which is a pixel electrode, is provided on the entire surface of the interlayer insulating film 500. The liquid crystal driving electrode 54 is connected to the drain wiring 536 through the contact hole 500a and is also provided above the source wiring 541 through the interlayer insulating film 500 and above the gate wiring Lt; / RTI > That is, the effective area (opening ratio) of the liquid crystal driving electrode 54 can be increased.

Here, the parasitic capacitance of the source wiring 541 and the gate wiring with respect to the liquid crystal driving electrode 54 can be reduced by forming the interlayer insulating film 500 thick (for example, several μm) . By setting the film thickness of the interlayer insulating film 500 as described above, the unevenness of the surface of the first glass substrate 51 on which a large number of active elements (TFTs 53) are formed is flattened, and the orientation of the reverse tilt domain It is possible to suppress the occurrence of defects.

In the liquid crystal panel having such a structure, the alignment film 56 is for controlling the liquid crystal alignment in which liquid crystal is aligned by applying a voltage between the transparent electrodes 54 and 55. Conventionally, the alignment film is controlled by rubbing, but a new alignment control technique has been attempted in recent years.

This is because a liquid crystal (liquid crystal) having orientation that is oriented by voltage application is provided between the first glass substrate 51 provided with the TFT element 53 and the second glass substrate 52 opposed to the first glass substrate 51 58 and a photoreactive material (ultraviolet ray reaction material) that causes polymerization in response to ultraviolet rays are sealed in the glass substrate 51, 52, and the liquid crystal panel is irradiated with ultraviolet rays to polymerize the ultraviolet reaction material, Tilt angle is imparted to the liquid crystal by fixing the direction of the liquid crystal (that is, a single molecule layer of the surface layer) in contact with the liquid crystal (see, for example, Patent Document 1).

According to this method, protrusions having an inclined plane, which was necessary for imparting a conventional pre-tilt angle, become unnecessary, so that the manufacturing process of the liquid crystal panel can be simplified. Therefore, the manufacturing cost and the manufacturing time of the liquid crystal panel can be reduced, and the shadows due to the protrusions are eliminated. Therefore, the aperture ratio is improved, and the power saving of the backlight is also advantageous.

With respect to a processing method of irradiating ultraviolet rays to a material (hereinafter also referred to as a liquid crystal including an ultraviolet reaction material) obtained by mixing a liquid crystal and an ultraviolet ray reaction material in a manufacturing technique of the liquid crystal panel for performing the new orientation control, Branch proposals are made.

In the " liquid crystal display device and its manufacturing method " described in Patent Document 2, a liquid crystal display device which performs ultraviolet ray irradiation under the first condition and ultraviolet ray irradiation under the second condition, in which the polymerization rate is larger than ultraviolet ray irradiation under the first condition, A manufacturing method of a display device (see the description of paragraph 0012 etc.) has been proposed. Concretely, ultraviolet irradiation is performed under the condition that the irradiance and the integration intensity are larger than the first condition in the second condition.

In this manner, in the ultraviolet ray irradiation under the first condition, since the polymerization is relatively gentle, the occurrence of alignment abnormality can be suppressed, and thereafter, a liquid crystal layer having no or no alignment abnormality can be obtained . In the ultraviolet irradiation under the second condition, it is described that it is preferable to increase the ratio of the low wavelength component near 310 nm (see the description of paragraph 0037 and the like).

In the " liquid crystal display device and its manufacturing method " described in Patent Document 3, it was found that it is better to irradiate ultraviolet rays cut in a short wavelength region of less than 310 nm by using a filter in order not to deteriorate the liquid crystal. However, if the intensity at a wavelength of 310 nm is completely made zero, it is difficult to obtain a desired liquid crystal alignment. Therefore, it is preferable to use a light source having an intensity of about 0.02 to 0.05 mW / cm ^{2 at a} wavelength of 310 nm "(see description in paragraph 0019, etc.).

In the " liquid crystal display device and its manufacturing method " described in Patent Document 4, although ultraviolet rays of short wavelength are advantageous in obtaining vertical orientation of liquid crystal in a short time, they tend to promote deterioration of liquid crystal molecules and the like, On the contrary, it is difficult to promote the deterioration of the liquid crystal molecules and the like, but it takes a long time to obtain the vertical alignment property of the liquid crystal (see the description of paragraph 0031 etc.), and the wavelength range of the ultraviolet ray to be irradiated is shown. However, in Patent Document 4, the temperature rise of the color filter is not mentioned.

Japanese Patent Application Laid-Open No. 2003-177408 Japanese Patent Application Laid-Open No. 2005-181582 Japanese Patent Application Laid-Open No. 2005-338613 Japanese Patent Application Laid-Open No. 2006-58755 Japanese Patent Application Laid-Open No. 2000-2887 International Publication No. 2009/016951 pamphlet

As described above, some proposals have been made for a treatment method of irradiating ultraviolet rays emitted from an ultraviolet light source to a material in which a liquid crystal and an ultraviolet reaction material are mixed. However, as a result of various experiments, The following findings are also obtained.

It has been found that there arises a problem that bubbles are generated in the liquid crystal in a part of the liquid crystal panel in which the liquid crystal panel using the liquid crystal including the ultraviolet ray reaction material is irradiated with ultraviolet rays and the alignment of the ultraviolet ray reaction material is controlled. Particularly, when an impact such as a vibration generated during transportation is applied to the liquid crystal panel, the occurrence of bubbles is remarkable. The mechanism of this bubble formation is considered as follows.

Fig. 12 shows the mechanism of foaming in the liquid crystal panel. Fig. 12 is an enlarged view of a part of the liquid crystal panel shown in Fig. 10, and the same components as those in Figs. 10 and 11 are denoted by the same reference numerals.

10, ultraviolet rays are irradiated from the side of the first glass substrate 51 on which a large number of active elements (the TFT 53 of FIG. 10) are arranged for each pixel, do.

Therefore, if the light emitted from the ultraviolet light source contains light having a wavelength belonging to the wavelength range absorbed by the interlayer insulating film (organic insulating film), it is possible to prevent the photodecomposition remaining on the interlayer insulating film (organic insulating film) Gas is generated.

The gas generated in the interlayer insulating film does not form bubbles at the time of generation. However, it spreads with time and passes through the alignment film 56 to penetrate the liquid crystal layer 58 as shown in Fig. 12 (a). The gas thus penetrated into the liquid crystal layer 58 is dissolved in the liquid crystal layer 58. The amount of the gas dissolved in the liquid crystal layer 58 increases with the lapse of the irradiation time of the light emitted from the ultraviolet light source.

When an impact is applied to the liquid crystal panel in such a state that a relatively large amount of gas is dissolved in the liquid crystal layer 58, the gas dissolved in the liquid crystal layer 58 is agglomerated, and as shown in Fig. 12 (b) The liquid crystal layer 58 grows into bubbles of a level size that can be visually confirmed.

As described above, it is difficult to remove bubbles generated in the liquid crystal layer 58, and the liquid crystal panel becomes defective. That is, since there is no liquid crystal in the bubble portion, no image is displayed in that portion.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a liquid crystal display device capable of suppressing the generation of gas in the interlayer insulating film and injecting the gas into the liquid crystal layer during light irradiation for polymerizing (curing) And an object of the present invention is to provide a manufacturing apparatus and a manufacturing method of a liquid crystal panel in which bubbles are hardly generated in a liquid crystal layer even when an impact is applied to a liquid crystal panel subjected to ultraviolet ray irradiation processing.

The inventors, after careful examination, found the following.

First, the ultraviolet ray reacting material to be mixed with the liquid crystal, which is generally used at present, was measured for absorbance with respect to the wavelength of light. Fig. 1 shows a graph of the absorbance of ultraviolet reaction material with respect to the wavelength of light, which is the result thereof. In this figure, the horizontal axis indicates the wavelength (nm) and the vertical axis indicates the absorbance (%).

As shown in the figure, in the ultraviolet ray-responsive material, light in a wavelength region of 370 nm or less is absorbed. In this case, the ultraviolet ray-responsive material generates a polymerization reaction. However, in practice, it has been found that the contribution to the polymerization reaction of light having a wavelength longer than 360 nm and longer wavelength than 360 nm, which dominantly contributes to the polymerization reaction, is remarkably small.

Meanwhile, the interlayer insulating film, which is an acrylic organic insulating film to which the present invention is applied, includes a photosensor, which generally absorbs light having a wavelength of about 430 nm or less, and as a result, generates a gas. In the present invention, the interlayer insulating film is an insulating film which includes a photosensitive unit, reacts with light irradiation, and can form a pattern by exposure and development processing. An acrylic insulating film is widely used as such an insulating film.

Here, in order to suppress the generation of bubbles in the liquid crystal layer of the liquid crystal panel to a minimum, it is conceivable to perform the ultraviolet ray irradiation treatment of the liquid crystal panel using the following ultraviolet light source.

That is, first, the ultraviolet light source emits light including ultraviolet light in a wavelength range contributing to the reaction of a photoreactive substance (ultraviolet ray reacting substance) in the liquid crystal panel.

Secondly, the ultraviolet light source absorbs light of a wavelength region that is absorbed by the interlayer insulating film and generates gas in the interlayer insulating film when the amount of irradiation (amount of exposure) of the light in the wavelength region is an irradiation dose sufficient for polymerization reaction of the photoreactive substance The amount of irradiation is such that the amount of the generated gas penetrating into the liquid crystal layer is such a gas amount that the foaming in the liquid crystal layer does not occur even when an impact is applied to the liquid crystal panel.

That is, assuming that the amount of energy required for the polymerization reaction of the photoreactive material in the liquid crystal panel is A, the amount of gas generated in the interlayer insulating film and permeating into the liquid crystal layer becomes the amount of gas reaching the foaming in the liquid crystal layer due to the impact applied to the liquid crystal panel (Energy amount) of light having a wavelength of 360 nm or less, which is dominantly contributed to the polymerization reaction, and b is an amount of irradiation (energy amount) of light having a wavelength of 430 nm or less absorbed in the interlayer insulating film, = A, it is preferable to perform the ultraviolet ray irradiation treatment of the liquid crystal panel by using an ultraviolet light source that emits light of b < B.

The amount of energy A required for the reaction of the photoreactive substance in the liquid crystal panel is required to be such that the amount of gas generated in the interlayer insulating film and penetrating into the liquid crystal layer becomes the amount of gas reaching the foaming in the liquid crystal layer due to the impact applied to the liquid crystal panel When the energy amount B is exceeded, it is difficult to make the foaming amount in the liquid crystal layer as small as possible. That is, in the present invention, it is essential to use as the photoreactive material in the liquid crystal panel those having characteristics satisfying the condition of B &gt; A.

The present inventors have investigated what kind of lamp can be used as a lamp capable of emitting the light as described above. As a result, it has been found that it is preferable to use a rare gas fluorescent lamp as described later. Further, the rare gas fluorescent lamp can change the wavelength range to be radiated.

For the three types of rare gas fluorescent lamps and metal halide lamps having different wavelengths, irradiation time t required for curing the photoreactive material, irradiance (mW / cm ² ) in the wavelength range of 360 nm or shorter, (MJ / cm ² ) under the condition of the irradiation time t and irradiation intensity (mW / cm ² ) in the wavelength range of the wavelength of 430 nm or less, irradiation amount (mJ / cm ² ) Respectively.

As a result, foaming occurred when a metal halide lamp was used, but generation of foaming was suppressed when a rare gas fluorescent lamp was used.

Based on the above, the present invention solves the problems as follows.

(1) a work stage holding an MVA type liquid crystal panel having an interlayer insulating film on an active element and containing a liquid crystal containing a photoreactive substance therein, and And a light irradiating unit for irradiating the light from the light irradiating unit to the liquid crystal panel supported by the supporting unit to react the light reactive material in the liquid crystal panel to form an alignment part inside the liquid crystal panel, , The following lamps are used as the lamp of the light irradiation unit.

When the irradiation amount a of the light in the wavelength region contributing to the reaction of the photoreactive substance in the liquid crystal panel is equal to the amount of energy A required for the reaction of the photoreactive substance, the irradiation amount b of the light in the wavelength region absorbed in the interlayer insulating film ) Has an emission spectrum which is smaller than the energy amount (B) necessary for the amount of gas generated in the interlayer insulating film that absorbs the light in the wavelength region to penetrate into the liquid crystal layer to reach the foaming in the liquid crystal layer Use a lamp.

(2) In the above (1), the amount of light (a) of the light in the wavelength region contributing to the reaction of the photoreactive substance in the liquid crystal panel is the amount of light in the wavelength region of 310 to 360 nm, (B) of the light in the wavelength region of 430 nm or less.

(3) In the above (1) and (2), a rare gas fluorescent lamp which does not emit light substantially 300 nm or shorter in wavelength is used as the lamp.

In the present invention, when the irradiation amount (a) of the light in the wavelength region contributing to the reaction of the photoreactive substance in the liquid crystal panel is equal to the energy amount (A) required for the reaction of the photoreactive substance, The amount of light irradiation b is smaller than the amount of energy B required for the amount of gas generated in the interlayer insulating film that absorbs the light in the wavelength region to penetrate into the liquid crystal layer to reach the foaming in the liquid crystal layer Since the liquid crystal panel is irradiated with an ultraviolet light source having a lamp having an emission spectrum, gas generation in the interlayer insulating film is suppressed when the photoreactive material (ultraviolet reaction material) is cured, Foaming can be suppressed to a minimum.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a diagram showing the absorbance of an ultraviolet reaction material with respect to the wavelength of light. Fig.
2 is a diagram showing a configuration example of an apparatus for manufacturing a liquid crystal panel of the present invention.
3 is a view showing a configuration example of a rare gas fluorescent lamp.
4 is a diagram showing another example of the structure of the rare gas fluorescent lamp.
Fig. 5 is a diagram showing the spectroscopic emission spectrum of the rare gas fluorescent lamp A. Fig.
Fig. 6 is a diagram showing the spectral radiation spectrum of the rare gas fluorescent lamp B. Fig.
Fig. 7 is a diagram showing the spectral radiation spectrum of the rare gas fluorescent lamp C. Fig.
8 is a view showing the spectral radiation spectrum of the rare gas fluorescent lamps A, B and C repeatedly.
9 is a diagram showing the spectral emission spectrum of a metal halide lamp.
10 is a diagram showing a configuration example of a liquid crystal panel.
11 is a diagram showing an example of the configuration of the active element and the periphery thereof in the case of providing the interlayer insulating film.
12 is a view for explaining the mechanism of foaming.

Fig. 2 shows a structural example of an apparatus (ultraviolet irradiating apparatus) for producing a liquid crystal panel according to the present invention.

The apparatus for manufacturing a liquid crystal panel (ultraviolet irradiation apparatus) of the present invention includes a light irradiation unit 1 and a work stage 2 on which a liquid crystal panel 3 is placed. The work stage 2 is provided with a mechanism 2a for applying a voltage to the liquid crystal panel 3 placed thereon. The light from the light irradiating unit 1 is irradiated to the liquid crystal panel 3 placed on the workpiece stage 2 while applying a voltage from the mechanism 2a for applying voltage as described in Patent Document 1.

The liquid crystal panel 3 has a structure in which a liquid crystal 3c containing an ultraviolet reactive material is sealed between two transparent substrates (organic substrates) 3a and 3b as described above, A plurality of active elements (TFT), a liquid crystal driving electrode, a color filter, and a transparent electrode (ITO) are formed on a glass plate as described above, and the periphery is sealed by the sealing agent 3d.

The light irradiation unit 1 includes a light source (lamp) 1a and a mirror 1b. The light source (lamp) 1 includes a rare gas fluorescent lamp Is used.

The light source 1a is supplied with power from the power source 1c and lights up. The power source 1c and the mechanism 2a for applying the voltage are connected to the control unit 4 and the control unit 4 controls the operation of the light source 1a so that the light source 1a is turned on, And controls the value and time of the voltage.

The liquid crystal panel 3 is placed on the workpiece stage 2 by a transport mechanism or the like (not shown). The control unit 4 applies a voltage from a mechanism 2a for applying a voltage and irradiates light from the light irradiation unit 1 to the liquid crystal panel. In addition to controlling the voltage and time to be applied to the liquid crystal panel, it is also possible to control the lighting time of the light source 1a to control the temperature of the liquid crystal panel while suppressing the rise of the ultraviolet reaction material (photoreactive material) And cured to give a pretilt angle to the liquid crystal as described above.

Here, as the ultraviolet ray reaction material mixed into the liquid crystal, it is preferable that the amount of energy (the above-mentioned A) required for curing the ultraviolet ray reaction material is such that the amount of gas generated in the interlayer insulating film and penetrating into the liquid crystal layer is A material having a property that the amount of energy B required for the amount of gas to reach the foaming in the liquid crystal layer is not exceeded is used.

3 is a diagram showing a configuration example of the rare gas fluorescent lamp. The rare gas fluorescent lamp has a tubular structure, and Fig. 3 shows a cross-sectional view taken along a plane including the tube axis. The rare gas fluorescent lamp 10 has a container (light emitting tube) 11 of a substantially double tube structure in which the inner tube 111 and the outer tube 112 are arranged on substantially the same axis, and both ends 11A And 11B are sealed so that a cylindrical discharge space S is formed therein. A rare gas such as xenon, argon, or krypton is sealed in the discharge space (S). The container 11 is made of quartz glass and has a low softening point glass layer 14 on the inner circumferential surface and a phosphor layer 15 on the inner circumferential surface of the low softening point glass layer 14. As the softened glass layer 14, for example, hard glass such as borosilicate glass or aluminosilicate glass is used. As the phosphor layer 15, for example, a cerium-activated magnesium lanthanum magnesium lanthanum (La-Mg-Al-O: Ce) phosphor is used. An inner electrode 12 is provided on the inner peripheral surface of the inner tube 111 and a net outer electrode 13 is provided on the outer peripheral surface of the outer tube 112. These electrodes 12 and 13 are arranged with the container 11 and the discharge space S interposed therebetween. The electrodes 12 and 13 are connected to the power supply unit 16 through the lead wires W11 and W12. When a high frequency voltage is applied from the power supply device 16, a discharge (so-called dielectric barrier discharge) is formed between the electrodes 12 and 13 through the dielectric layers 111 and 112, and in the case of xenon gas, Lt; / RTI &gt; The ultraviolet light obtained here is the excitation light of the phosphor. By irradiating the phosphor layer, ultraviolet light having a center wavelength near 340 nm is emitted.

Fig. 4 shows another configuration example of the rare gas fluorescent lamp. (A) is a cross-sectional view taken along a plane including a tube axis, and (b) is a cross-sectional view taken along line A-A of (a). 4, the lamp 20 has a pair of electrodes 22 and 23, the electrodes 22 and 23 are disposed on the outer circumferential surface of the container (light-emitting tube) 21, and the electrodes 22 and 23 And a protective film 24 is provided on the outer side. An ultraviolet reflection film 25 is provided on the inner surface opposite to the light emitting direction side of the inner peripheral surface of the container 21 (see Fig. 4 (b)) and a low softening point glass layer 26 is provided on the inner periphery thereof, The phosphor layer 27 is provided on the inner peripheral surface of the softening point glass layer 26. The other constitution is the same as that shown in Fig. 3, and the same is true for the gas to be enclosed in the discharge space S in the vessel 21 and the phosphor used for the phosphor layer 27. When a high frequency voltage is applied to the electrodes 22 and 23, a dielectric barrier discharge is formed between the electrodes 22 and 23, and ultraviolet light is generated as described above. As a result, ultraviolet light having a center wavelength of about 340 nm is generated from the phosphor layer, and this light is reflected by the ultraviolet reflection film 25 and emitted from the opening portion where the ultraviolet reflection film 25 is not provided do.

5 to 7 show spectral emission spectra of rare gas fluorescent lamps used in the examples of the present invention. The horizontal axis indicates the wavelength (nm) and the vertical axis indicates the spectral irradiance (μW / cm ² / nm).

As described above, the rare gas fluorescent lamp can change the wavelength range to be radiated by combining the fluorescent material. Figs. 5 to 7 show spectral emission spectra of three types of rare gas fluorescent lamps A, B and C having different wavelength ranges to be emitted. Lt; / RTI &gt; 8 shows the spectral spectra of the three kinds of rare gas fluorescent lamps A, B and C repeatedly shown for comparison.

In the rare gas fluorescent lamp A, a rare gas containing xenon as a main component is encapsulated in the discharge space S. The phosphor layer 15 is made of cerium-resolved magnesium lanthanum (La-Mg-Al-O: Ce ) Phosphors (abbreviated as LAM phosphors) are used.

In the rare gas fluorescent lamp B, a rare gas containing xenon as a main component is enclosed in the discharge space S. The cerium-activated barium magnesium-cerium (Ce-Mg-Ba-Al-O) A phosphor (abbreviated as CAM phosphor) is used.

On the other hand, in the rare gas fluorescent lamp C, a rare gas containing xenon as a main component is enclosed in the discharge space S. A cerium-activated yttrium phosphate (YPO: Ce) phosphor (abbreviated as YPC phosphor) is used for the phosphor layer 15 have.

As shown in Fig. 8, in the wavelength range of 310 nm to 360 nm, the wavelength ratio on the shorter wavelength side is [rare gas fluorescent lamp A]> [rare gas fluorescent lamp B]> [rare gas fluorescent lamp C].

As shown in Fig. 5 to Fig. 7, the rare gas fluorescent lamp emits light dominated by the ratio of the irradiance in the wavelength range of 360 nm or less as the light in the wavelength range of 450 nm or less.

That is, if the radiation intensity in the wavelength region of 360 nm or less and dominantly contributing to the polymerization reaction is a _li (W / cm ² ), the radiation intensity of the radiation intensity in the wavelength region of 430 nm or less absorbed by the interlayer insulating film is b _Li (W / cm ² ), b _li > a _li, but the difference between b _li and a _li is small.

Therefore, when the irradiation amount of light in the wavelength region of 360 nm or less at the irradiation time t is a ₁ (= a _{li ×} t (J / cm ² )) and the irradiation amount of the light in the wavelength region of 430 nm or less absorbed by the interlayer insulating film is b ₁ = b _{li x} t (J / cm ² )), b _l > a _l, but the difference between b _l and a _l is small.

On the other hand, FIG. 9 shows a spectral radiation spectrum (using a filter) of a metal halide lamp in the case where light in a wavelength region of 450 nm or more is cut by a filter as a comparative example. The horizontal axis indicates the wavelength (nm) and the vertical axis indicates the spectral irradiance (μW / cm ² / nm).

The metal halide lamp is conventionally used in an ultraviolet irradiation apparatus, and contains mercury and a metal therein.

As can be clearly seen from Fig. 9, the metal halide lamp of the above-described configuration is light in a wavelength range of 450 nm or less, particularly light in which the ratio of the irradiance in the wavelength range of 360 to 430 nm is dominant Radiate.

Namely, the radiation intensity in the wavelength region of 360 nm or less, which dominantly contributes to the polymerization reaction, is a _mi (W / cm ² ), and the radiation intensity of the radiation intensity in the wavelength region of 430 nm or less b _mi (W / cm ² ), b _mi > a _mi, but the difference between b _mi and a _mi becomes significantly larger than that of the rare gas fluorescent lamp.

Therefore, a _m (= a _mi x t (J / cm ² )) of the light in the wavelength region of 360 nm or less at the irradiation time t and an irradiation amount of the light of the wavelength region of 430 nm or less absorbed in the interlayer insulating film are b _m = b _mi x t (J / cm ² )), b _m > a _m, but the difference between b _m and a _m is large, and compared with the case of the rare gas fluorescent lamp, │b _m -a _m │> b _l -a _l |.

Therefore, when the light from the lamp is irradiated to the liquid crystal panel so that the irradiation amount (energy amount) a of light having a wavelength of 360 nm or less, which dominantly contributes to the polymerization reaction, becomes equal to the energy amount A required for the reaction of the photoreactive substance in the liquid crystal panel , The irradiation time at this time is t1, the irradiation amount (energy amount) of light having a wavelength of 430 nm or less absorbed by the interlayer insulating film emitted from the rare gas fluorescent lamp is B1 (= b _li x t1) When B2 (= b _mi x t 1) is an irradiation amount (energy amount) of light having a wavelength of 430 nm or less absorbed by the interlayer insulating film, B2> B1.

When the amount of energy required to cause the amount of gas generated in the interlayer insulating film to reach the foaming in the liquid crystal layer due to impact after penetration into the liquid crystal layer is B, When a rare gas fluorescent lamp as described above is used as the light source of the ultraviolet irradiator, B1 < B is satisfied, and when the metal halide lamp as described above is used, B < B2.

That is, by irradiating the liquid crystal panel with the light emitted from the ultraviolet irradiator equipped with the rare gas fluorescent lamp as described above, the orientation of the liquid crystal (that is, one molecule layer of the surface layer) contacting the glass substrate is fixed by polymerizing the ultraviolet reaction material When the pretilt angle is imparted to the liquid crystal, the gas generation amount in the interlayer insulating film on the active element is suppressed, and the foaming in the liquid crystal layer can be remarkably suppressed. Therefore, problems in manufacturing the liquid crystal panel can be suppressed.

In addition, since the light having a wavelength of 300 nm or less is absorbed by the liquid crystal and the amount of irradiation may increase, damage to the liquid crystal may occur. Therefore, it is preferable that the lamp is a lamp which does not emit light substantially 300 nm or less in wavelength. In a rare gas fluorescent lamp, light having a wavelength of 300 nm or less rarely radiates.

In order to confirm the effect of the present invention, the following experiment was conducted to verify the wavelength emitted from the lamp and the presence or absence of foaming of the liquid crystal panel. Table 1 shows the results.

Table 1 shows the relationship between the irradiation time tc necessary for curing of the monomer (ultraviolet ray reaction material) when three liquid crystal panels having different compositions of the interlayer insulating film were irradiated using the three kinds of rare gas fluorescent lamps A to C and the metal halide lamp 2tc, the integrated irradiance in the wavelength range of 310 nm to 360 nm, and the light in the wavelength range of 310 nm to 360 nm at a time tc and a period of time 2 tc (the irradiation time is 2 times the irradiation time required for curing of the monomer) , The total irradiated light intensity in the wavelength range of 310 to 430 nm and the irradiated light intensity in the wavelength range of 310 nm to 430 nm at the time tc and 2 tc are irradiated for only the irradiation amount b and the time tc, And whether or not the foaming occurred in the liquid crystal layer after the light irradiation for only the time 2 tc was given to the liquid crystal panel. The irradiation amount is a value obtained by multiplying the irradiance by the irradiation time.

[Table 1]

The thickness of the liquid crystal layer (cell gap) in the three liquid crystal panels is all 4 탆. The interlayer insulating films S1, S2, and S3 of the three liquid crystal panels are all acrylic organic insulating films having a photosensitive wavelength of 365 nm and a film thickness of 3 m. However, the kind and concentration of the photosensor included in the interlayer insulating film are different from each other.

Here, spectral emission spectra of the rare gas fluorescent lamps A to C are as shown in Figs. 5 to 7 above. The spectral emission spectrum (using a filter) of the metal halide lamp is as shown in Fig.

In the case of the metal halide lamp used in this experiment, the time tc required for curing the monomer is 240 seconds, the integrated irradiance of light in the wavelength range of 310 nm to 360 nm is about 19.8 mW / cm ² , the integrated irradiance of the light in the wavelength range of 310 nm to 430 nm Was 96.5 mW / cm &lt; ^{2 &} gt ;. The irradiation amount of the light in the wavelength region 310 nm to 360 nm at the time tc was 4752 mJ / cm ² , and the irradiation amount of the light in the wavelength region 310 nm to 430 nm was 23160 mJ / cm ² . On the other hand, over exposure time 2tc is 480 seconds, the amount of irradiation of light in a wavelength range 310nm~360nm in time 2tc is 9504mJ / cm ^2, irradiation amount of light in a wavelength range 310nm ~ 430nm was 46320mJ / cm ^2.

Under these conditions, foaming occurred in all of the three liquid crystal panels using the interlayer insulating films S1, S2, and S3, which are acrylic organic insulating films having different compositions from each other.

That is, in the case of the metal halide lamp used in this experiment, the value of the irradiation amount a _tc = 4752 mJ / cm ² of the light in the wavelength range of 310 nm to 360 nm at the time tc corresponds to the energy amount A required for the polymerization reaction of the photoreactive substance in the liquid crystal panel (A _tc = A). The amount of light b _tc = 23160 mJ / cm ² , which is absorbed by the interlayer insulating film at the time tc, in the wavelength region of 310 nm to 430 nm is equal to the amount of gas generated in each interlayer insulating film S1, S2, by an impact applied to the volume of gas there is leading to foaming in the liquid crystal layer is considered that the same or higher than the amount of energy of each Ba, Bb, Bc necessary _{(b tc ≥Ba, b tc ≥Bb} , b tc ≥Bc ).

The value of the irradiation amount a _2tc = 9504 mJ / cm ² of the light in the wavelength region 310 nm to 360 nm at the over-irradiation time 2tc exceeds the energy amount A (a _2tc > A), and the wavelength region 310 nm (B _2tc > Ba, b _2tc > Bb, b _2tc > Bc) of the energy b _2tc = 46320 mJ / cm ² of the light having the wavelength of 430 nm is naturally higher than the energy amounts Ba, Bb and Bc respectively.

On the other hand, in the case of the rare gas fluorescent lamp A, the time tc required for curing the monomer is 180 seconds, the integrated irradiance of the light in the wavelength range of 310 nm to 360 nm is 16.4 mW / cm ² and the integrated irradiance of the light in the wavelength region of 310 to 430 nm 23.6 mW / cm &lt; ^{2 &} gt ;. The irradiation amount of the light in the wavelength region 310 nm to 360 nm at the time tc was 2952 mJ / cm ² , and the irradiation amount of the light in the wavelength region 310 to 430 nm was 4248 mJ / cm ² . On the other hand, over exposure time 2tc is 360 seconds, the amount of irradiation of light in a wavelength range of 310nm ~ 360nm in time 2tc is 5904mJ / cm ^2, a wavelength range of 310nm ~ 430nm light irradiation amount was 8496mJ / cm ^2.

Under these conditions, no foaming occurred in all of the three liquid crystal panels using the respective interlayer insulating films S1, S2, and S3.

That is, in the case of the rare gas fluorescent lamp A used in this experiment, the value of the irradiation amount a _tc = 2952 mJ / cm ² of the light in the wavelength region 310 nm to 360 nm at the time tc is smaller than the energy amount A required for the polymerization reaction of the photoreactive substance in the liquid crystal panel (A _tc = A). The amount of light b _tc = 4248 mJ / cm ² in the wavelength region of 310 nm to 430 nm absorbed in the interlayer insulating film at the time tc is equal to the amount of gas generated in each interlayer insulating film S1, S2, by the applied shock there is a gas flow leading to foaming in the liquid crystal layer is considered to fall below the amount of energy required Ba, Bb, Bc, respectively _{(b tc <Ba, b tc} <Bb, b tc <Bc).

The value of the irradiation amount a _2tc = 5904 mJ / cm ² of the light in the wavelength region 310 nm to 360 nm at the over-irradiation time 2tc exceeds the energy amount A (a _2tc > A), but the wavelength region 310 nm The amount b _2tc = 8496 mJ / cm ² of light with a wavelength of 430 nm is considered to be below the amounts of energy Ba, Bb and Bc, respectively (b _2tc <Ba, b _2tc <Bb, b _2tc <Bc).

In the case of the rare gas fluorescent lamp B, the time tc required for curing the monomer is 330 seconds, the integrated irradiance of the light in the wavelength region 310 nm to 360 nm is 11.6 mW / cm ² , the integrated irradiance of the light in the wavelength region 310 nm to 430 nm is 18.2 mW / cm &lt; ^{2 &} gt ;. The irradiation amount of the light in the wavelength region 310 nm to 360 nm at the time tc was 3828 mJ / cm ^2, and the irradiation amount of the light in the wavelength region 310 nm to 430 nm was 6006 mJ / cm ² . On the other hand, over exposure time 2tc is 660 seconds, the amount of irradiation of light in a wavelength range of 310nm ~ 360nm in time 2tc is 7656mJ / cm ^2, irradiation amount of light in a wavelength range 310nm ~ 430nm was 12012mJ / cm ^2.

Under this condition, no foaming occurred in the liquid crystal panel using the interlayer insulating film S1 when light was irradiated for a time tc required for curing the monomer, and for light irradiation for an over-irradiation time 2tc. On the other hand, for each liquid crystal panel using the interlayer insulating films S2 and S3, foaming did not occur when light irradiation was performed for a time tc required for curing the monomer, but foaming occurred when light irradiation was performed for an over-irradiation time 2tc.

That is, in the case of the rare gas fluorescent lamp B used in this experiment, the value of the irradiation amount a _tc = 3828 mJ / cm ² of the light in the wavelength range of 310 nm to 360 nm at the time tc is smaller than the energy amount A required for the polymerization reaction of the photoreactive substance in the liquid crystal panel (A _tc = A). The amount of light b _tc = 6006 mJ / cm ² in the wavelength region of 310 nm to 430 nm absorbed by the interlayer insulating film at the time tc is equal to the amount of gas generated in each interlayer insulating film S1, S2, by the applied shock there is a gas flow leading to foaming in the liquid crystal layer is considered to fall below the amount of energy required Ba, Bb, Bc, respectively _{(b tc <Ba, b tc} <Bb, b tc <Bc).

The value of the irradiation amount a _2tc = 7656 mJ / cm ² of the light in the wavelength region 310 nm to 360 nm at the over-irradiation time 2tc exceeds the minimum amount of energy A required for the polymerization reaction of the photoreactive substance in the liquid crystal panel (a _2tc &_Gt; A), and the amount of light b _2tc = 12012 mJ / cm ² in the wavelength region of 310 nm to 430 nm in this period is the amount of gas generated in the interlayer insulating film S 1 and penetrating into the liquid crystal layer, It is considered that the amount of energy Ba required to reach the amount of gas reaching the foaming in the step of FIG. However, the irradiation dose b _2tc = 12012 mJ / cm ² is an amount of energy necessary for the amount of gas generated in the interlayer insulating films S 2 and S 3 to penetrate into the liquid crystal layer to become the amount of gas reaching the foaming in the liquid crystal layer due to the impact applied to the liquid crystal panel Bb, and Bc, respectively (b _2tc <Ba, b _2tc ≥Bb, b _2tc ≥Bc).

In the case of the rare gas fluorescent lamp C, the time tc required for curing the monomer is 480 seconds, the integrated irradiance of the light in the wavelength range 310 nm to 360 nm is 8.5 mW / cm ² , the integrated irradiance of the light in the wavelength range 310 nm to 430 nm is 10.3 mW / cm &lt; ^{2 &} gt ;. The irradiation amount of the light in the wavelength region 310 nm to 360 nm at the time tc was 4080 mJ / cm ^2, and the irradiation amount of the light in the wavelength region 310 nm to 430 nm was 4944 mJ / cm ² . On the other hand, over exposure time 2tc is 960 seconds, the amount of irradiation of light in a wavelength range of 310nm ~ 360nm in time 2tc is 8160mJ / cm ^2, irradiation amount of light in a wavelength range 310nm ~ 430nm was 9888mJ / cm ^2.

Under these conditions, no foaming occurred in each of the liquid crystal panels using the interlayer insulating films S1 and S2, even when light was irradiated for a time tc required for curing the monomer, or when irradiated with light for an over-irradiation time 2tc. On the other hand, in the liquid crystal panel using the interlayer insulating film S3, foaming did not occur when light irradiation was performed for a time tc required for curing the monomer, but foaming occurred when light irradiation was performed for an over-irradiation time 2tc.

That is, in the case of the rare gas fluorescent lamp C used in this experiment, the value of the irradiation amount a _tc = 4080 mJ / cm ² of the light in the wavelength region 310 nm to 360 nm at the time tc is smaller than the energy amount A (A _tc = A). The amount of light b _tc = 4944 mJ / cm ² in the wavelength region of 310 nm to 430 nm absorbed by the interlayer insulating film at the time tc is equal to the amount of gas generated in each interlayer insulating film S1, S2, by the applied shock there is a gas flow leading to foaming in the liquid crystal layer is considered to fall below the amount of energy required Ba, Bb, Bc, respectively _{(b tc <Ba, b tc} <Bb, b tc <Bc).

The value of the irradiation amount a _2tc = 8160 mJ / cm ² of the light in the wavelength region 310 nm to 360 nm at the over-irradiation time 2tc exceeds the energy amount A (a _2tc > A), but the wavelength region 310 nm The irradiation amount b _2tc = 9888 mJ / cm ² of the light of? 430 nm is the energy required for the amount of gas generated in the interlayer insulating films S1 and S2 to penetrate into the liquid crystal layer to become the amount of gas reaching foaming in the liquid crystal layer due to the impact applied to the liquid crystal panel The amounts Ba and Bb, respectively. It is considered, however, that the amount of gas generated in the interlayer insulating film S3 and penetrating into the liquid crystal layer is equal to or more than the amount of energy Bc required for the amount of gas to reach the foaming in the liquid crystal layer due to the impact applied to the liquid crystal panel ( _b2tc &_Lt; Ba, _b2tc < Bb, _b2tc &gt; Bc).

The above is summarized as follows. The thicknesses of the interlayer insulating films S1, S2, and S3 (each having a thickness of 3 mu m), which are acrylic organic insulating films having different compositions from each other, were used for three liquid crystal panels each having a thickness of 4 mu m, When three kinds of rare gas fluorescent lamps A to C were used when light emitted from three kinds of rare gas fluorescent lamps A to C and a metal halide lamp was irradiated, foaming did not occur in the liquid crystal layer even when the liquid crystal panel was impacted . However, when a metal halide lamp was used, a shock occurred in the liquid crystal panel to cause foaming in the liquid crystal layer.

In the case of a liquid crystal panel using the interlayer insulating film S1, in the case of the liquid crystal panel, the threshold for the amount of energy Ba that foaming occurs, and is present between the ^{12012mJ / cm 2 ~ 23160mJ / cm} 2, using the interlayer insulating film S2, foaming threshold amount of energy Bb generated is, exists between the ^{9888mJ / cm 2 ~ 12012mJ / cm} 2, the case of a liquid crystal panel using the interlayer insulating film S3, the threshold of the amount of energy of Ba which foaming occurs, 8496mJ / cm ² ~ Cm &lt; ² &gt; and 9888 mJ / cm &lt; ² &gt;.

Further, the irradiation amount a _tc (= the amount of energy A required for the polymerization reaction of the photoreactive substance in the liquid crystal panel) in the wavelength range of 310 nm to 360 nm at the time tc is [the rare gas fluorescent lamp A] <the rare gas fluorescent lamp B < Rare-gas fluorescent lamp C] <metal halide lamp]. However, it is considered that the larger the short wavelength ratio, the faster the reaction rate and the smaller the required irradiation amount.

1:
1a: Light source (lamp)
1b: mirror
1c: Power supply
111: Inner tube (dielectric)
112: outer tube (dielectric)
11A and 11B:
2: Workstage
2a: a device for applying a voltage
3: liquid crystal panel
3a, 3b: light-transmitting substrate (glass substrate)
3c: liquid crystal containing ultraviolet reactive material
3d: sealant
4:
10, 20: lamp
11, 21: container (luminous tube)
12, 13: electrode
22, 23: electrode
14, 26: low softening point glass layer
15, 27: Phosphor layer
16: Power supply
24: Shield
25: ultraviolet ray reflection film
S: Discharge space
W11, W12: Lead wire
50: liquid crystal panel
51: first glass substrate
52: second glass substrate
53: TFT
54: Electrode for liquid crystal driving
55: transparent electrode (ITO)
56: alignment film
57: Color filter
58: liquid crystal (liquid crystal layer)
59: Seal
531: Gate
532: Gate insulating film
533: semiconductor layer
534: Source
535: Drain
536: drain wiring
541: source wiring
500: interlayer insulating film (organic insulating film)
500a: contact hole

Claims (4)

A work stage holding an MVA type liquid crystal panel having an interlayer insulating film on an active element and having a liquid crystal containing a photoreactive substance sealed therein; and a light source for irradiating the liquid crystal panel held on the work stage with light from a lamp And irradiating the light from the light irradiation unit to the liquid crystal panel held on the work stage to react the light reactive material in the liquid crystal panel to form an alignment part in the liquid crystal panel In the apparatus,
The lamp of the light irradiating unit is a rare gas fluorescent lamp. When the amount of light (a) of the light in the wavelength region contributing to the reaction of the photoreactive substance in the liquid crystal panel is equal to the amount of energy (A)
It is necessary that the amount of irradiation (b) of the light in the wavelength region absorbed in the interlayer insulating film is such that the amount of gas generated in the interlayer insulating film that absorbs the light in the wavelength region penetrates into the liquid crystal layer to reach foaming in the liquid crystal layer (B) is smaller than the energy amount (B) of the liquid crystal panel. The method according to claim 1,
(A) of the light in the wavelength region contributing to the reaction of the photoreactive substance in the liquid crystal panel is an amount of light in the wavelength region of 310 to 360 nm, and the amount (b) of light in the wavelength region absorbed by the interlayer insulating film is 430 nm or less Of the light in the wavelength region of the liquid crystal panel. The method according to claim 1 or 2,
Wherein the rare gas fluorescent lamp does not emit light substantially having a wavelength of 300 nm or less. An MVA type liquid crystal panel having an interlayer insulating film on the active element and containing a liquid crystal containing a photoreactive material is irradiated with light to react the photoreactive material in the liquid crystal panel to form an alignment portion in the liquid crystal panel A method of manufacturing a liquid crystal panel,
When the irradiation amount (a) of the light in the wavelength region contributing to the reaction of the photoreactive substance in the liquid crystal panel is equal to the amount of energy (A) required for the reaction of the photoreactive substance,
It is necessary that the amount of irradiation (b) of the light in the wavelength region absorbed in the interlayer insulating film is such that the amount of gas generated in the interlayer insulating film that absorbs the light in the wavelength region penetrates into the liquid crystal layer to reach foaming in the liquid crystal layer And irradiating the liquid crystal panel with light by using a rare gas fluorescent lamp so as to be smaller than the energy amount (B).

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